
Thunder in the Valley is a triathlon and duathlon race on May 15, 2027 in Terre Haute, IN, with entry fees from $65 to $100.
USAT CERTIFIED EVENT
USAT membership will be required at registration or you can opt for a 1Day USAT race license.
Thunder in the Valley Triathlon is 41 years old in 2026. Athletes will also get top notch swag with custom die cast finisher medals and awards, swim caps, and a super cool Thunder in the Valley t-shirt.
Sprint Triathlon Distances 500Μ SWIM 20K BIKE 5K RUN
Duathlon Distances 1.6K RUN 20K BIKE 5K RUN
This triathlon will begin at 8am with a 500 meter swim in the calm Hawthorn Lake. After a quick lakeside transition athletes will head out for a smooth, fast 20k bike course with rolling hills that brings them back to the transition area. Athletes will then run on a shaded, flat out and back 5k course before returning to the finish line. This race is the perfect race for the new triathlete looking for their first triathlon, or the seasoned athlete looking for their first race of the season. For 41 years, Thunder has been the race to kick-off triathlon season!
The Duathlon will begin with a 1 mile out and back run to transition before heading out on the 20k bike course. This race is held around and within beautiful Hawthorn Park with great competition for beginners and experienced athletes. Awards and post race refreshments following the race.
The guarantee t-shirt cutoff is April 23rd at 11:59pm. If you sign up after this date, there is not a guarantee you will get a shirt, even though we will order some extras.
USAT rules state that competitors may wear wetsuits if the water temperature is 78 degrees or lower.
USAT rules also state that if the water temperature is between 78.1 – 83.9 degrees, competitors may wear wetsuits but will not be eligible for awards or USAT ranking points.
USAT rules also state that if the water temperature is 84 degrees or higher, wetsuits may not be worn.
It's too far out for a forecast, so here's what weather on this date is normally like in the area. A race day forecast will replace this as race week approaches.
Typical High
75°
Typical Low
53°
Based on US Climate Normals data from Terre Haute Caa Ap, 3 mi from the venue.
Population
58,491
as of 2023
City Elevation
490 ft
Nearest Airport
IND
Indianapolis International Airport · 61 mi
Time Zone
Eastern Time
From Endurance Grid
A mid-size host city. Enough lodging and amenities to keep race weekend easy, without big-city sprawl.
Every finish line starts with a single decision. Claim your spot at Thunder in the Valley, put it on the calendar, and turn “someday” into a start date.
184
Days to train
Plan your training, log every workout, and track your progress all the way to race day in the Endurance Grid app.


Thunder in the Valley
May 15, 2027